Surfboard

ABSTRACT

A surfboard having a rigid forward hull portion and a resilient bottom tail portion which flexes upwardly in use in response to water pressure on the undersurface thereof. A spring assembly biases the left and right side of the tail portion downward independently and a stop means defines the position of maximum upward deflection of the tail portion. The stop means is adjustable to provide various positions of maximum deflection, and the adjustment can be accomplished either manually or by means of a radio-controlled motor mounted in the surfboard and operated by a palm-sized transmitter strapped to the hand of the surfer.

United States Patent Tinkler et a1.

wemm

Sept. 2, 1975 SURFBOARD [76] Inventors: Robert C. Tinkler; Michael R.

Tinkler, both of 3275 Jamaica Ct., San Diego, Calif. 92108 [22] Filed: July 5, 1973 [21] Appl. No.: 376,341

[52] US. Cl 9/310 E [51] Int. Cl. A63C 15/00 [58] Field of Search 9/310 R, 310 A, 310 B, 9/310 C, 310 D, 310 E, 310 F, 310 G [56] References Cited UNITED STATES PATENTS 3,317,937 5/1967 Gallagher 9/310 R 3,543,315 12/1970 Hoffman 9/310 E 3,657,753 4/1972 Le Blane 9/310 F Primary Examiner-Trygve M. Blix Assistant ExaminerStuart M. Goldstein Attorney, Agent, or FirmRalph S. Branscomb [5 7] ABSTRACT A surfboard having a rigid forward hull portion and a resilient bottom tail portion which flexes upwardly in use in response to Water pressure on the undersurface thereof. A spring assembly biases the left and right side of the tail portion downward independently and a stop means defines the position of maximum upward deflection of the tail portion. The stop means is adjustable to provide various positions of maximum deflection, and the adjustment can be accomplished either manually or be means of a radio-controlled motor mounted in the surfboard and operated by a palmsized transmitter strapped to the hand of the surfer.

7 Claims, 8 Drawing Figures PATENTED 21975 3 902 207 sum 2 0F 2 SURFBOARD BACKGROUND OF THE INVENTION It is well known to surfers that different surf conditions call for surfboards of different design and for this reason many accomplished surfers own a variety of boards. Individual technique also dictates to some extent the most appropriate board for a particular surfer.

Even during the same ride, it would be advantageous to have a board with a variable hydrodynamic surface to accommodate the various water conditions encountered when different surfing maneuvers are performed. For example, a straight-tailed board, while providing a great deal of lift and being most appropriate for straight runs parallel to the wave, will dig into the water and dissipate the Surfers accumulated momentum when a turn or cut across the concave face of the wave is attempted. Conversely, a board with an upswept tail will plane nicely and preserve momentum when cutting across the waveface, but on a straight run the curved bottom does not provide the necessary lift.

SUMMARY OF THE INVENTION The present invention is a surfboard with a bottom tail section in the form of a resilient deflection panel which assumes a variable camber in response to the water pressure thereunder and in accordance with lim its established by the surfer. The deflection panel is downwardly biased by a spring assembly mounted in the hull, and a stop means prevents upward deflection of the panel beyond a point which is determinable by an adjustment of the stop means. The adjustment can be made manually, in which case. The maximum camber is temporarily set to accommodate the taste of the particular suffer and the general surf conditions. or it can be made almost instantaneously during a ride by means of a radio control unit to alter the boards surface in accordance with the particular maneuver being performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of the rear portion of a surfboard incorporating the adjustable unit; FIG. 2 is a top plane view of the board;

FIG. 3 is an enlarged sectional view taken on line 33 of Ciagure 2;

FIG. 4 is a rear elevation viewed of the board, partially cut away and illustrating a typical deflection;

FIG. 5 is an enlarged sectional view taken on line 55 of FIG. 2;

FIG. 6 is a top plan view of the board with power drive means installed;

FIG. 7 is an enlarged side elevation view, partially cut away, of the configuration of FIG. 6; and

FIG. 8 is a perspective view of a hand held control unit for the powered unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The surfboard has a flattened elongate hull 10 defining a deck 12, a bottom 14 and two side rails 16. The deck and rails are rigid, and the bottom, which is rigid in its forward portions, extends into a resilient rearward deflection panel 18. The rails extend rearwardly from the nose of the surfboard and terminate at the forward end of the deflection panel to allow the panel to flex. The hull is preferably constructed of honeycomb plastie, which is a honeycomb material interleaved between two layers of sheet plastic, in accordance with current surfboard construction methods. The deflection panel can be made by removing the honeycomb material from between the two outer sheets in the rear bottom portion and replacing the honeycomb with plastic or fiberglass laminations which decrease in number rearwardly to create a resilient panel of decreasing thickness.

The rear panel of the deck 12 extends partway over the deflection panel and defines a slightly raised, rigid cowling 20 which may be strenghtened by the addition of longitudinal beams or struts molded to the underside thereof. A substantially enclosed housing 22, having two side walls, a top wall 24, a bottom wall 26, a front wall 28 and a rear wall 30, is mounted to the inside of the cowling and is preferably dimensioned to provide a clearance space-between the bottom wall 26 and the deflection panel 18.

The housing contains a spring assembly which controls to some extent the movement of the deflection panel. The effectuate this control two rocker arms 32 are fulcrummed to two support arms 34, which are mounted on a base plate 36 secured to the bottom wall 26. The after ends of the rocker arms project through openings in the rear wall 30 and are connected to two laterally-spaced rearwardly disposed mounting brackets 38 on the deflection panel by means of doubly pivoted connecting rods 40.

Two vertical, laterally spaced shafts 42 are rotatably mounted between the top wall 24 and the base plate 36. Riders 44 are slideably journaled on smooth-surfaced cylindrical enlargements 46 of the upper portions of the shafts and provide a bearing surface for the overlying forward end of the rocker arms which are forked to straddle the enlargements 46. The riders each have a collar 48 by which the riders are supported on coil springs 30 which extend to the base plate 36 and are centered at their lower extremities by means of centering discs 52 which fit within the springs and are secured to the base plate. In order to preserve the working mechanism in dry condition, a flexible, water-tight form-fitted tail piece 54 is fitted over the delfection panel and rocker arms, extending forwardly along the sides of the cowling to meet the aftermost ends of the rails 16. All junctions between the tail piece and the rest of the surfboard are sealed.

In use, the deflection panel will assume a camber, as illustrated in FIG. 3 in phantom, that will vary in accordance with the speed the board is moving through the water, the distribution of the surfers weight, and the particular maneuver being made. The springs 50, acting through the rocker arms 32, will provide a constant downward bias on the deflection panel to resist deflection and return the panel to the flat position when the pressure is relieved. Since the bias is applied independently to the right and left sides of the panel, the panel may twist as well as deflect in response to certain actions of the surfer. While making a tight right-hand U- turn into the concave face of a wave, the right rear rail of an ordinary prior-art surfboard would dig into the water, providing lateral resistance in competition with the stabilizing fin and producing a drag that dissipates the accumulated momentum of the surfer. In contrast, while making the same turn with the present surfboard, the right side of the deflection panel flexes, as illustrated in FIG. 4, the full resistance of the water to lateral motion being thrown the stabilizing fin 53 which bends reed-like under the stress to further reduce drag. The resulting configuration of the deflection panel is a convex surface which fits into the concave wave face and planes much as a flat surfboard planes on flat water.

It is not always desireable that the deflection panel be allowed to flex upwardly to the full extent permitted by the springs 50. To provide an upper limit on the displacement of the panel, a stop means is provided comprising two cups 56, one of which is secured on each of the shafts 42, and two short coiled buffer Springs 58 which seat in the cups and are centered about the rc spective shafts by the retaining lips of the cups. The lower edges of the riders 44 are beveled to seat in the tops of the buffer springs so that as the deflection panel moves upwardly and the forked forward ends of the rocker arms 32 force the riders down, the riders seat in the buffer springs, which provide stiff opposition to further travel by the riders.

The limitation of the upper displacement of the deflection panel allows the surfer to maintain a relatively flat bottom to the board to adapt the board to the particular surfing conditions, the tastes of the surfer, or the manuevers to be made in the water. All of these factors may charge, and in order to accommodate the board to variations, the stop means is made adjustable as described hereinafter.

The lower portions of the shaft 42 are threaded as at 60, and a bare unthreaded portion 62 is provided between the threaded portions and the enlargements 46 on each shaft. The cups 56 have an axial threaded hole through which the threaded portions of the shafts are secured, and pins 64, which are secured in the centering discs 52, pass up through the cups and riders to stabilize those two elements against rotation. It will be clear that as the rotatable shafts 42 are turned, the cups will travel up or down, depending on the direction of rotation, so that the limiting position is variable. When the cups are driven upward past the threaded portions 60 onto the unthreaded portion 62 of the shafts, they will freewheel without climbing further. Upon reverserotation of the shafts, the buffer springs force the cups into re-engagement with the threaded portions.

The buffer springs in addition to cushioning the rocker arms against shock, also provide a means of adjusting to some extent the tension exerted by the springs against the rocker arms.

The rotation of the shafts, and thus the adjustment of the position of the cups 56, may be accomplished in a number of ways. As disclosed, manual tuning knobs or a radio controlled motor may be used. Both methods may be used in the same surfboard, but in the preferred arrangement two production models are provided, each embodying one of the adjustment means.

In the manual model, each of the shafts 42 projects through the deck, which is recessed at those places to provide countersinks for two tuning knobs 66 which are mounted on the ends of the shafts. The knobs, being countersunk, do not significantly disrupt the contours of the deck, so the surfer may at times stand on the knob area. Hollows 68 provide a means of gripping and turning the knobs. The holes in the deck, or in the top wall 24 of the housing 22, through which the shafts pass, are provided with bearing seals 70 which allow rotating of the shafts and prevent the entry of water into the working mechanism.

The radio controlled version is superior in operation, if more costly to produce, in that the sufer can control or tune" the deflection panel during a ride. In this model, the shafts do not necessarily penetrate the deck 12, although in the drawings the radio controlled version is shown only in combined form with the manually operated knobs. The shafts are provided just below the socket mountings with juxtaposed axially mounted spur gears 72, and a reversible motor 76, mounted in the rear portion of the housing 22 has a gearbox 78 with a projecting worm drive 80 which engages both spur gears and drives them simultaneously, so that the portions 60 on the shafts must be oppositely threaded in order that the cups 56 rise and fall together. A microswitch, not shown, is provided at the bottom of one of the shafts and is positioned to be actuated by one of the cups 56 and its lowermost position to deenergize the motor. A radio receiver, diagrammatically, illustrated at 82, is operably wired to the motor, which is powered by a battery pack indicated at 84. A palm-sized transmitter 84, which can be strapped to the surfer s hand as shown in FIG. 38, is provided with two buttons which transmit forward and reverse signals to the receiver.

In production, it may be desirable to manufacture the spring assembly, stop means and the control for the stop means as a single unit, mounted in the housing 22, and insertable in surfboards which are made as described above to receive such a unit. The manually tuned model and the radio controlled version could be made as separate units, or with both control means integrated into a single unit. In either case, surfboards of a single design can be made which will receive any of the units alternatively.

I claim:

1. A deflection unit for insertion in a rear portion of a surfboard, said surfboard having a hull with a rigid portion and a resilient bottom tail portion capable of upward deflection in response to water pressure on the underside thereof;

said unit including stop means to define a position of maximum upward deflection of said resilient bottom tail portion, said stop means being adjustable so that said position of maximum upward deflection is variable.

2. A surfboard comprising:

a. a flattened elongated hull, said hull having:

i. a rigid forward portion;

ii. a resilient aftermost bottom portion comprising a deflection panel having a left and a right side and being capable of upward deflection in response to water pressure on the underside thereof; and

b. two spring assemblies mounted in said hull which bias said left and right sides independently against upward movement to permit upward deflection of each of said sides independently of the other of said sides.

3. The structure of claim 2 and including a stop means to define a position of maximum upward deflection of said deflection panel, said stop means including at least one buffer spring to cushion said deflection panel against shock upon reaching said position of maximum upward deflection.

4. The structure of claim 2 and including a stop means to define a position of maximum upward deflection of said deflection panel, and including an adjustmounted in said surfboard to drive said adjustment means.

7. The strcture of claim 6 and including a radio control receiver operably connected to said motor, and a radio control transmitter to be carried by the surfer. 

1. A deflection unit for insertion in a rear portion of a surfboard, said surfboard having a hull with a rigid portion and a resilient bottom tail portion capable of upward deflection in response to water pressure on the underside thereof; said unit including stop means to define a position of maximum upward deflection of said resilient bottom tail portion, said stop means being adjustable so that said position of maximum upward deflection is variable.
 2. A surfboard comprising: a. a flattened elongated hull, said hull having: i. a rigid forward portion; ii. a resilient aftermost bottom portion comprising a deflection panel having a left and a right side and being capable of upward deflection in response to water pressure on the underside thereof; and b. two spring assemblies mounted in said hull which bias said left and right sides independently against upward movement to permit upward deflection of each of said sides independently of the other of said sides.
 3. The structure of claim 2 and including a stop means to define a position of maximum upward deflection of said deflection panel, said stop means including at least one buffer spring to cushion said deflection panel against shock upon reaching said position of maximum upward deflection.
 4. The structure of claim 2 and including a stop means to define a position of maximum upward deflection of said deflection panel, and including an adjustment means for said stop means so that the position of maximum upward deflection of said deflection panel is variable.
 5. The structure of claim 4 wherein said adjustment means is manually operable.
 6. The structure of claim 4 and including a motor mounted in said surfboard to drive said adjustment means.
 7. The strcture of claim 6 and including a radio control receiver operably connected to said motor, and a radio control transmitter to be carried by the surfer. 